On the night I did some live demos (perilous!) which, at one point, did in fact go awry. Luckily it turned out to be a small issue with an Ansible module. The beauty of working with a Git checkout of Ansible is you can quickly swap versions, which is precisely what I did. Checkout of previous release branch, and all was well again.
The presentation contains a link to the code used to build the demos, but you can head straight there now if you like.